Abstract
Impact of out-of-hospital cardiac arrest (OHCA) in the Lombardy Region (Italy): Analysis of data collected by the Emergency Medical Services (EMS) Registry
Authors
Villa G.F.*, Minoretti V.**, Pagliosa A.*, Canevari F.*, Manera M.***, Solaro N.***, Kette F.*, Salmoiraghi M.*, Zoli.A.*, Executive Staff of AATs*. * AREU [Emergency Medical System Trust] Lombardia - ** Medicine Faculty, University of Milano-Bicocca *** Department of Economics, Management and Statistics, University of Milano-Bicocca
Background
Out of Hospital Cardiac Arrest has become a global public health emergency in Western Countries. No data on OHCA in the Lombardy Region have been previously collected..
Design and setting
Observational, retrospective, analytic, single cohort study on the Lombardy population in the Lombardy territory.
Objective
The study aimed at analyzing out-of-hospital cardiac arrest (OHCA) in the population of the Lombardy region, which is a significant sample of the Italian population in terms of quantity and quality. The study was based on the data collected by Medical Dispatch Centers and field rescue medical teams.
Methods
The data on out-of-hospital cardiac arrest in the Lombardy population (9,924,447 people) were collected via Emma Web Operating System and uploaded in the database. The data referred to an overall 30-day period divided as follows: 14-23 October 2013, 14-23 January and 14-23 March 2014. The hospital data and those gathered at the patients' homes were provided by the receiving hospital departments. All the cardiac arrest cases rescued by the Emergency Medical Services (EMS) were considered first; then, in accordance with Utstein Style guidelines, the study excluded the cardiac arrest cases that had not received resuscitation by rescue personnel (269), the cardiac arrest cases with non cardiac aetiology (74) and unwitnessed cardiac arrest cases (176).
Results
Of the 946 OHCA cases initially considered, the study analyzed 428 events (70.9%) of presumed cardiac aetiology. In accordance with Utstein Style evaluation parameters, the outcomes analyzed were sustained Return of Spontaneous Circulation [ROSC] (107 cases – 25%), Survival Events in the Emergency Room (95 cases – 22.2%), Survival Events at 24 hours (88 cases – 20.6%) and at 30 days (46 cases – 11%). The study then evaluated the effect on the outcome of all the variables that occurred throughout the medical event, considering both the unchangeable factors and those strictly depending on the rescue. The most statistically significant variables among those analyzed were: advanced age, correlated to a higher incidence of cardiac attack and a lower ROSC (p<0.001) rate; the quality of the presenting rhythm, in that the rhythms that can be defibrillated have a higher correlation with ROSC (p<0.001) and Survival Events (SE) at 30 days (p<0.05); the rescue medical means with a higher ROSC rate in those cases where the Basic Life Support (BLS) ambulances (volunteer rescuers) were supported by Advanced Life Support (ALS) doctors' cars or nurses' vehicles (p<0.001); early bystander-assisted resuscitation, with Public-Access Defibrillation (PAD) in 1.6% and start of Cardiopulmonary Resuscitation (CPR) in 30% of cases that results in higher ROSC rate (p<0.05) and identification of a rhythm that can be defibrillated (26.4% vs 16.1%). The results of an analysis on the timing, although not supported by statistical data, shows that reduced rescue times (particularly in urban areas) are associated with a greater possibility of identifying rhythms that can be defibrillated. The other situations analyzed, which however have not produced statistically significant results, are the neurological outcome, the effect of seasons and the use of therapeutic hypothermia in the hospital setting. The national and international comparison of the rescue costs is interesting, as those in Lombardy are the lowest compared to other countries.
Conclusions
Apart from the importance of some variables in influencing cardiac arrest outcome, specific differences have been found between the data collected in urban areas (Medical Dispatch Center located in urban areas, SOREU Metropolitana) and those gathered in extra-urban areas (Medical Dispatch Centers located in rural areas, SOREU Provinciali), in particular with regard to the management of rescue operations. The analysis has conditioned the introduction of a new approach to the management of the Medical Dispatch Center for the intervention of doctors' cars and nurses' vehicles that will be studied in the next future. Moreover, the importance of additional training and dissemination of information in the lay population for early rescue and outcome improvement were confirmed.